Reading the model code
BD6A- Family segment. The 6A here is the balance-current class, not a pack rating: what governs JK-BD6A24S12P is 0.6A active balancing, and the class comes with the family rather than being chosen separately.
24S- Maximum cells in series, which is roughly 76.8V nominal with LiFePO4 cells. It is a ceiling: nothing is wasted by running fewer cells.
12P- Continuous discharge position. The spec table on this page lists 120A, and that is the figure to size cable, terminals and the protective device against.
What actually changes between these codes
Move across to JK-BD6A24S10P and the only thing that changes inside BD6A is continuous current — 120A here against 100A there, with the 24S ceiling and the 0.6A balance rate identical on both. US$0.73 separates the two at the base configuration. That makes it a load calculation rather than a feature decision.
Same current, different ceiling: JK-BD6A20S12P runs to 20S where this board stops at 24S, which is 76.8V nominal here against 64V there. Choose on the cell stack, because no setting converts one into the other.
JK-BD4A24S12P is the other candidate for the same pack: 24S, 120A, 0.4A balancing rather than 0.6A. It sits US$2.90 below this listing at the base configuration. If the cells are matched and the duty cycle leaves idle time, the cheaper of the two is the right answer; if they are not, no protection setting replaces balance current.
26 BD6A codes are priced here, from US$47.98 for JK-BD6A17S6P to US$175.68 for JK-BD6A32S15P; JK-BD6A24S12P is 19 of that set at US$76.96 before configuration options. The spread across the family is a ratings spread rather than a margin spread, so quote the cheapest code that clears the calculation.